Davit.



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DAVIT.

APPLICATION FILED DEC. H, I915- Patented Aug. 29, 1916.

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CHRISTIAAN VISSER, OF NEW YORK, N. Y.

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Specification of Letters Patent.

Patented Aug. 29, 1916.

Application filed December 14, 1915. Serial No. 66,850.

To all whom it may concern: 7

Be it known that I, CHRIs'rIAAN Vrssnn, a subject of the Queen of theNetherlands, residing at New York, in the county and State of New York,have invented certain new and useful Improvements in Davits, of whichthe following is a full, clear, and exact specification.

This invention relates to davits for supporting and lowering life-boatsfrom the decks of larger vessels, and it has for its object to providemechanical means for turning the davits for swinging the life-boats overthe side of the ship, in order that this operation may be positivelyaccomplished in spite of the listing of the ship as often occurs after acollision or injury to the hull of the ship. When the davits have to beswung out by hand, the listing of the ship one way makes it practicallyimpossible to launch the life-boats from the upper side of the deck, andmany lives have been lost on this account. It is the aim of the presentinvention to provide means which will make it possible to launch thelife-boats from the upper side of the deck at such times and thus renderthe full quota of life-boats useful in such cases of emergency.

Other objects will appear as the description proceeds.

The invention will be first hereinafter describedin connection with theaccompanying drawings, which constitute a part of this specification,and then more specifically defined in the claims at the end of thedescription.

In the accompanying drawings, wherein similar reference characters areused to designate corresponding parts throughout the several views:Figure 1 is'a broken elevation of the middle portion of a davit,constructed substantially in accordance with this invention and showingthe mechanical means for turning the same for swinging the life-boatover the side of the ship. Fig. 2 is a sectional View on the line II-Hof Fig. 1, and Fig. 3 is a diagrammatic plan view of a pair of davits,showing the arrangement of the operating cranks and how said davits areswung out one at a time for launching a life-boat.

In Fig. 1, 1 designates the boat deck of the ship, and 2 and 3 areplates secured above and below the same, respectively, by bolts & forjournaling the middle portion of the davit 6. The upper plate 2 ispreferably provided with an upwardly extending sleeve 5 to give a betterbearing for the davit. As illustrated, the base of the davit extendsdown through the boat deck and lower plate 3 to the main deck (notshown). To prevent axial movement of the davit, it is provided with acircumferential groove 8 a short distance below the bottom plate 3, anda collar 7, having screws or bolts 9 extending into said groove, isplaced around the middle portion of the davit and in contact with theunder face of said plate 3.

Spaced some distance above the deck, a plate 10 is supported rigidlyfrom the plate 2 by rods 11, preferably two in number, one on eitherside of the davit, as shown in Fig. 2. The lower ends of said rods areprovided with shoulders 12 to rest upon the top surface of the plate 2,and with screw threaded extremities 13 to engage sockets in said plate.The upper ends of the rods 11 are also shouldered at 14: and have theirextremities passed through the plate 10 and screw threaded, as at 15, toreceive binding nuts 16.

Between the plates 2 and 10 the davit is screw threaded, as at 17, andaround said screw threaded portion is fitted a collar 18 having aninteriorly screw threaded passage to fit the threads 17, and otherpassages 19 through which the rods 11 extend as a means for guiding saidcollar 18. An internally screw threaded bushing 20 is carried by thecollar 18 and through it runs a screw shaft 21 journaled at 22 in theplate 2, and at 28 in a bushing 24: in the plate 10. A beveled pinion 25is keyed to the shaft 21 and meshes with a pinion 26 on a shaft 27 whichis journaled in a downwardly bent portion 28 of the plate 10. The shaft27 is fitted with a crank 29 having an operating handle 30.

From the foregoing it will be seen that when the crank 29 is turned inone direction, the collar 18 will be moved upwardly, while the reverseturning of said crank will lower the collar 18, and that the movement ofsaid collar will cause the davit to turn by reason of the threads 17. InFig. 8, the davit 6 is shown as it is used with a second davit which isconstructed exactly like the davit 6 except that the thread thereon isinclined in the reverse direction from the thread 17 on the davit 6, inorder to make the davits turn toward each other, as indicated in the Itwill be noted that the operating cranks 29 are arranged out of the wayand do not interfere with the movement of the boat in launching thesame.

Havingv thus described my invention, what I cla m as new. and desire'tosecure by Letters Patent of the United-States is 1. The combination witha davit having screw threads thereon,rof a collar having acorrespondingly threaded passage fitted around'the threaded portion ofthe davit,

means for movingsaid collar axially along the davitfor turning thelatter, and means for preventing said collar turning with the davit.- i

2. The combination with a davit having screw threads thereon, of -acollar having a Cepiesef this patent may be obtained for f ve centseach, by addressing the Commissioner of Patents,-

7 Washington, D. C.-

davit is oper ated to swing out the other end of the boat.

correspondingly threaded passage fitted around the threaded portion ofthe davit, said collar having another screw threaded passage therein, ascrew shaft running throu h said latter aassa e means for V b b 7turning said shaft to move the collar axially along the davit and thuscause the latter to -turn, and means for preventing said collar fromturning.

CHRISTIAAN VISSER.

a davit having

